Common Fossils of Kansas--Pennsylvanian Plants

All of the specimens in this figure are Pennsylvanian plants.
They grew in swampland forests which were populated not by the
deciduous trees we know today, but
by large, soft-tissued trees
represented now by the small ground pines and scouring-rushes.
Calamites (1 in the photograph) was a giant (to 30 feet
high) scouring-rush or horsetail. From the horizontal joints in
the stem (see drawing) grew a whorl of simple leaves of which
Annularia (4) is an example. Plentiful also in the forests
were huge-scale trees such as Lepidodendron (6). Their
leaves left scars resembling scales. Some of these scale trees
reached 100 feet in height and exceeded four feet in diameter.

Pecopteris (2a, b), Neuropteris (3a, b), and
Alethopteris (5) were all Pennsylvanian ferns.
Alethopteris, a seed fern, and Pecopteris, a true
fern, differ from Neuropteris, another seed fern, in
that the bases of the pinnules, the leaflike portions of the
frond, are broadly attached to the stem, whereas in
Neuropteris, the pinnules are constricted to a point at
the bases. (All Upper Pennsylvanian, eastern Kansas)